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Ian Gills
10-01-2009, 05:47 AM
11 story building.

Over 80 wall hung toilets and 30 urinals.

Where would the vent be and how big would it be?

Would I find a 4 inch piece of PVC sticking out of the roof if I ventured up there?

If it's any bigger, what would stop people falling in? :eek:

jimbo
10-01-2009, 06:13 AM
You would probably find two 4's.

Anyone who gets up on the roof of an 11 story building either knows how to look out for himself, or deserves to fall in!

hj
10-01-2009, 06:18 AM
The number of stories and/or the number of fixtures by themselves mean nothing. HOW the fixtures are arranged on the various floors determines the pipe sizes and their arrangement. You will NOT find a 4" PVC sticking out of the roof, because VERY FEW, if any, codes allow ANY plastic piping over three stories. The fact that very few people would fit into a pipe smaller than 12" is what keeps them from falling in.

FloridaOrange
10-01-2009, 06:19 AM
11 Stories would likely be a Solvent system.
(2) 4's or maybe 6's (although unlikely) depending on how they designed it and if they were accounting for future uses.
You may also find a few 3's if they have typical fixture locations away from the main plumbing stack(s).

Sovent design manual (http://www.sovent.com/downloads/SE%20SOVENT%20DESIGN%20MANUAL%20101o%20new011007.p df)

Ian Gills
10-01-2009, 06:42 AM
How is water pressure maintained 11 stories up?

FloridaOrange
10-01-2009, 06:50 AM
Pump(s) with PRV's at each floor. Maybe a tank on the roof.

Ian Gills
10-01-2009, 06:51 AM
Wow. I'm gonna go DIY commercial style.

Why doesn't the hot water take ages to come up to the 9th floor, if I am the first one to wash my hands in the morning? I sure get hot water quicker than in my single story rambler at home?

FloridaOrange
10-01-2009, 07:17 AM
You might have a heater close (mechanical closet nearby?) or the whole building has a recirc system.

loafer
10-01-2009, 08:14 AM
Wow. I'm gonna go DIY commercial style.

Why doesn't the hot water take ages to come up to the 9th floor, if I am the first one to wash my hands in the morning? I sure get hot water quicker than in my single story rambler at home?

In large hotels the hot water is constantly circulated through a loop, similar to a force hot water heating system. Branches from the circulating loop supply each room which results in virtually instant hot water. Other large buildings may use similar techniques.

hj
10-01-2009, 08:34 AM
SoVent is a very UNCOMMON system, therefore, an 11 story building would not necessarily have one. There are many ways to supply water to the various floors. A pump in the basement with PRV's at each floor, or a few PRV's each serving several floors, a tank on the roof downfeeding the water system, or a hybrid with the pump feeding the lower floors and the tank taking care of the upper ones. And, these are just a few of the many possible combinations.

Ian Gills
10-01-2009, 08:38 AM
Fascinating. Is it the same sort of issue for all buildings three-stories and over or are there other cut-offs?

For example, above 50 stories do new things come into play with plumbing?

Terry
10-01-2009, 05:51 PM
One of the local hotels here uses the Sovent system.
Staying there, I noticed the trap making noise like it was being siphoned.
A lot a noises coming from it.

Ian Gills
10-01-2009, 05:54 PM
My work would not let me on to the roof to have a look. The guard asked if I was going to jump or fly?

If I had a helicopter they could make special arrangements.

So I guess DIY, commerical-high rise style is a no no.

That's a shame.

Let's all DIY high in the sky!

hj
10-02-2009, 07:49 AM
Height creates to problems. Water lines develop higher pressure, and drain lines develop excessive velocity. Both situations require special features to minimize their effects. WHAT is done may be unique to each building because there are many ways to ameliorate the effects of height. Imagine the pressure to get water to the top of the Burg Dubai 2900 foot high building, or the terminal velocity of water draining from a top floor toilet.